Checkers Plugin for Tkabber

Installation:
Just put all checkers directory to $HOME/.tkabber/plugins (on UNIX),
to %APPDATA%\Tkabber\plugins (on Windows), or to
$HOME/Library/Application Support/Tkabber (on MacOS X) directory. Then after
Tkabber restart new submenu "Games" with "Checkers" option will appear in
roster user context menu.

Checkers rules included in distribution are taken from
http://ourworld.compuserve.com/homepages/Arthur_H_Olsen/checkers.htm
